Since Federal laws and regulations promulgated thereunder require that closures as referred to satisfy certain testing procedures before being approved for sale in commerce, there has been a resurgence in recent years of concepts for child-resistant closures, especially those which are simple and have features rendering operation obvious to an adult but not to a child and involve low cost. An important factor is the cost of molds for fabricating the part. Ideally, a one-piece closure of proper construction will most likely be the cheapest to produce and the simplest to operate.
The larger volume of conventional, re-usable caps for containers are those held on the neck of the container by screw-threads, and by this I include bayonet forms of attachment. The remainder is made up of caps which are engaged with a bead-and-groove feature. In any case engagement is the result of simple rotation or thrusting and pulling of the cap.
I am aware that closures functioning similarly to that disclosed herein have been known, e.g. in U.S. Pat. Nos. 810,736 and 1,341,177 but these have proved unreliable, expensive and difficult to operate. The present disclosure relates to improvements in such closures.